Well, so far, its a pretty good illusion.
There is a lot more trust as the basis of this system then most would ever want to admit to.
However, since we have invented money, given any amount of time, a group of people will recreate money. Just because it is so much easier to handle transactions. (i.e. prison societies)
Haha. That was great.
The necessity for money stems from the illusion of scarcity that is sold to us.
Not really. Lets say there is a river right over there, a short walk. So, there is lots of water over there, but there is a shortage of water over here, where you are. So, you can go get some water yourself, or try to get someone to bring water to you. Now it could be that you are going to use the water to make moonshine, and so bubba, which bubba would really like, so bubba will exchange his time to go get the water for your time spent stoking the still.
Money can be considered to be a tally system for exchange of other people's time.
And time although not really scarce, their is definitely a finite amount of it, and a problem of only being able to do one thing at a time.
Unless I am misunderstanding this, there is no need for money in the example you have put forth. Bubba can simply get the water as he is more fit to do, in return for some of the moonshine, that he is unable to make.
You are correct, that there is no need. However, when you get to more then a few exchanges and more than a few people, then the tokenization of favors comes in handy.